Apparatus for the formation of nitric acid or hydrochloric acid



APPARATUS. FOR THE Forum-:ON or NITRIC AOID 'on HYDROCHLORIC ACID FiledJan. 13, 1925 E I K* ao 5 Patented Aug. 7, 1928.

UNITED STATES PATENT OFFICE.

GIUSEPPE GUADAGNI, OF TUEIN, ITALY.

, 4 .APPARATUS FOR. THE FOBMATION OF NITIRIC ACID OB HYDROCHLORIC ACID.

Application me& January 13, 1925, Serial No. 2,201, and in GermanyDecember 12, 1924.

lower openings of the cast` iron containers,`

while-when HCl isnanufactured-the bisulphate is caused to act with afresh quantity of salt at a higher temperature in another part of thefurnace (in the muflle) nearer to the firing, until it is converted intoneutral sulphate of soda, while at the same time a new formation ofhydrochloric acid gas takes place The charging of salt and discharging'of the products of the'above named reactions are effected atintervals ofgenerally six hours; these Operations require time and handwork and meana loss of heat and acid gases and harm to the operator. health, as thework must becarried on in rooms saturatcd With hot and irritating acidvapours and poisonous gases.

All these inconveniences are removed by the automatically andcontinuously working apparatus forming the object of this inventionpermitting of the commerical formation of nitric .acid or hydrochloricacid and sodinin bisulphate.

This apparatus is substantially constituted by an elliptical container,(in which the sulphuric acid is caused to act on common salt or 'sodiumnitrate) and a hopper through which the salt is fed into the containcrby means of a short and wide convcyor screw. A suitable device, (towhich the movement of said conveyor screw is transmited) serves to admitinto the container the quantity of sulphuric acid thatis necessary fordissociating the salt issuing from the conveyor screw in the unit oftime. A pipe reaching near the bottom of the container and issuingthrough the wall thereof at a certain height serves for the continuousdischarge to the outside of the sodium bisulphate that is graduallyformed. The ellptical container is tight closed by means of a coverconsisting of refractory, preferably siliceous, material that will notbe de-' teriorated by the acid at a high temperature. Saidcover isprovided on each side with an opening', the :front opening serving forthe admssion of salt and .acd 'and the back opening for the discharge ofthe acid hot gases that will be conveyed into the con-` densing andabsorbing apparatus through suitable pipes. i

It will be seenthat' the greater is the distance between the inlet ofthe reactin'g material and the outlet of the bisulphate the longer willbe the time during which said materials react on one ahother under theaction of a high temperature. Therefore, the reaction being improved,the conveyor screw may be' driven at a higher speed in the unit of timeand the efliciency of the apparatus will be correspondingly increased.

vided with a cover 4 of siliceous material. a

tube 2 discharging the bisulphate and a tube 3 through which thecontainer may be cleaned during an interru tion of work. At the frontside of the retractory cover 4 s Secured a cast iron tower carrying acast iron filling hopper 6,'through which a predetermined quantity ofsalt is fed into the container 1 by means of a conveyor screw 5 drivenby a worm wheel 7 in the inlet tube 8. At the same time a predetermined.quan-' tityof sulphuric acd or 66B.) is introduced into the container 1through a pipe 10 by means of a feeder comprising a cou le of scoops 14Suspended at the ends o a rocker to which is centrally secured an arm 11connected by means of a rod to a crank pin 9 fixed to the worm wheelkeyed on the conveyor shaft.

Each scoop is provided with a long delivery pipe ending in a spout whichrests on the wall of a container 12, the acid in which is kept at aconstant level by the overflow A a tower of refractorymaterial isarranged I 3 c regulating 'apparatus 14' `r as well as theend o i tuberoject' out of the oven. he s wherein the gradually evolved gase's arecel o lected and wherefrom the quartz tubes 16 are branched leading thesaid gases into the 1 usual condensing 'and' absorbing apparatus. Fromsaidtube 2 the sodium bisulphate formed during the dissociation issuescontin- 16' ually. The sz'eiof the container, as well as- ;the distancebetween the salt admission point and the' dischargeof 'the slphate aresuch I that :the reacting masses in the container under' the action ofthe beat remain a longer 20 time than wouldbenece'ssarv for theformation of the gas (HCl or V essary pureness, hardness and pulverizingproerty.'-

he 'above described mechanical ap'paratus s applied in a suitablefurnace, wherein the container is completely surrounded by hot air andhot gases,

while the hopper contain- .ingn the salt, the

conte-hier 12 and the acid V are outside the oven and the tower 15-forthe' evolved acid gases phurc acid in excess, issuing from V letter aconstant and uniform tem 0,), in order conduit for to impart to the ssing bisulphate' the nec- 'its inlet .end dipping into the quid mass ateeting agents whereby a complete react-ion of said -agents is insured,the other end of the sulphate discharg of theflcontainer 12 of .the acidreg'ulating apparatus is returned wagons. 40

- i What I claim is:

Apparatus-for the contnuous production V of hydrochlori'c or nitric acidand sodium bisulphate, comprising an oven, a single elongated'containermounted wholly within the latter, a cover of'fire-proof material tightlyclosing the cbntainer and also wholly within the. oven 'whereby burntgases circulate all about the container and ensure within the rature, asingle Conduit 'at one endof t e cover' through which the re-actingagents are fed into* the Container, a delivery tower for the {v aseousdischarge at the other end,`said conuit and tower projecting outwardlythrough the oven roof means at the outer end of said i eeding there-actin agents in regulated quantities, and a tube or the con- 'tinuousdischarge of the bisul hate, having a point near the bottom of thecontaier substantially below the point of gaseous dis'- charge, andremote from the inlet for the resaid tube Yassing through the containerat y the norma liquid product level therein to maintain said level.constantby continuous discharge.

- In testimony that I claim the foregoing 70 as my 'inventici I havesigned my name.

USERPE GUADAGNI.

